Printing telegraph exchange system



May 30, 1933. A. F. CONNERY PRINTING TELEGRAPH EXCHANGE SYSTEM Filed May 14, 1931 ATTORNEY INVENTOR ALDER F. CONNERY 7 BY Patented May 39, 1933 UNITED STATES earsnr cl ric]:

ALDER F. CONN-ERY, OF BROOKLYN, NEW YORK, ASSIGNOR T INTERNATIONAL COM- I MUNIOATIONS LABORATORIES, INC, OF NEW YORK, N. Y., A CORBORATION'OF' NEW I YORK IRIN'TING TELEGRAPH EXCHANGE SYSTEM Application filed May 14, 1931; Serial No. 537,366.

This invention relates generally to printing telegraph exchange systems, and relates more particularly to printing telegraph exchange systems in which subscribers stations associated with different central stations' can be interconnected by means of manual switchboards and cooperating switching apparatus placed at the several central stations.

Heretofore it has been customary to establish communication circuits between subscribers stations and printers at a central station by means of a manual concentration board and its associated cord. circuits. A system of this type is disclosed in U. S. Patent 1,773,952 issued on August 26, 1930 in the name of A. F. Connery. Such sys terms are limited in scope, for they can be used for local service between subscribers stations and printers at a single central station only. The present invention, which is an improvement upon the system disclosed in the Connery patent, is designed to provide a system of greater flexibility and Wider scope, by permitting connection not only between subscribers stations and printers at a single central station but also between subscribers stations associated with separate central stations.

Broadly considered, the invention contemplates the extension of a communication circuit from a calling subscribers station to a concentration board at a first central station, and then through a switching trunk to a toll board at the same station, over a toll line to a toll board at a second central station, through a switching trunk to a concentration board at that station, and thence to a called subscribers station.

One of the principal objects of the invention is to provide means for interconnecting subscribers stations associated with separate central stations by means of manual switchboards and cooperating switching apparatus placed at these stations.

Another object is to provide the calling and supervisory means necessary for the proper establishment and supervision of a connection between remote subscribers sta tions.

A further object is to provide means for employing a printer in supervising the connection without interfering with circuits actually set up.

Other objects will become apparent from the followin detailed description and the accompanying drawing, and will be more particularly pointed out; in the appended claims. J

Fig. 1 illustrates. schematically the ar-' rangement of a printing telegraph exchange system embodying applicants invention:

Fig. 2 illustrates in detail theapparatus and circuits at a single central station.

Referring to 1, A and D represent s'ubscribers stations, while B andC represent central stations. In one of itsaspects, the present invention contemplates the extension ofa communication circuit from the subscribers' station A to the associated central station B, and thence to the central station C from which this circuit is extended to the called subscribers station D. Obviously, the invention also contemplates the establishment of a communication circuit in the reverse direction.

Referring now to Fig. 2, S represents a subscribers station connected by a line, 1, to a central station, V represents a manual concentration board to which are connected a plurality of subscribers lines, as l, which extend from subscribers stations as S. T represents a central station printer cord circuit adapted to be connected through the concentration board V tothe subscribers station S; lV represents a switching trunk adapted to extend any of the subscribers lines, as 1, to a toll board Y. Associated with the toll board Y is a cord circuit X and a halfduplcx set Z. It is apparent that in place of this half-duplex set Z. It is apparent that in place of this half-duplex set a'full duplex set, a carrier channel terminal set or any well known type of telegraph repeater might readily be substituted. If a full duplex set is used, two entire circuits as shown in Fig. 2 would be used for the sending and receiving legs respectively. To

ing trunk W, a single cord circuit X, etc,

I station printer is shown at 36, while the transmitting contacts are shown at 87. At 38 is shown a non-polarized or neutral relay wmding whlch may become short-circuited by the contacts of a polarized relay 39. Re-

lay 39 is equipped with a biasing spring and is connected in hne 1, so that when either positive current or no current is supplied from the central station its contacts keep the winding of relay 38 shunted out. The transmission of messages is accomplished by making and breaking the positive line current supplied from the central station, and under these conditions relay 38 is unopera-ted because its windings are short-circuited and the current to the printer motor 40 is therefore uninterrupted. lVhen it'is desired to stop motor 40, negative current is supplied from the central station. In response to this reversal of current, polarized relay S9 operates and removes the shunt from relay 38 which thereupon becomes energized, interrupting the current to driving motor 40. Negative currentis supplied from the battery associated with the concentration board V at the central station only when the sub scribers station printeris not in use. At the subscribers station a break key 42 is also provided in the line circuit'l.

The concentration board V has a line jack 2 with which are associated a calling lamp 3, a normally energized line relay 4 and a subscribers line 1. The line 1 extends from the subscribers stations, to contact B in the line jack, winding A of the line relay 4, through a resistance to grounded negative battery-5. Upon the opening of the line 1, line relay 4 releases, closing both its C and D contacts, the closure of the former serving to shunt winding A of line relay 4 to prevent the reenergization of that relay when line 1 is again closed, and the closure of the latter contact serving to complete a circuit for calling lamp 3. This circuit may be traced from grounded positive battery 41, contact D of line relay 4, contact A of jack 2, and lamp 3 to ground. The sleeve of the jack 2 is connected through winding B of line relay 4, resistance to grounded positive battery 41.

The printer cord circuit T is provided with a cord 43 adapted to be connected to the jack 2 of the concentration board V. The printing magnets 44 of the cord circuit printer, the transmitting contacts 45, and the relay 46 are connected in series through the tip and sleeve of the plug 48. The relay 46, when energized, permits the condenser 47 to discharge through the windings of a relay 48 to operate the latter relay. When operated and locked relay 48 completes a circuit for the printer motor 49, and extinguishes lamps 50 and 51 which are normally lighted. Lamp 50 is located at the concentration board V, and lamp 51 is located at the operators set. The. function of the lamp 50 is to notify the concentration board operator whether or not the printer operator is busy. The function of the lamp 51 is to give the printer operator an indication that the non-busy signal is appearing at the concentration board on lamp 50.

The switching trunk W terminates in the jacks 10 and 11 at the toll board. This trunk includes a plug 6 comprising a tip and sleeve, a sleeve relay 7, supervisory lamps 8 and 9, and conductors extending to monitor trunk jack 10 and jack 11 at the toll board. Positive battery is connected to the tip of plug 6 over a circuit extending from grounded positive battery 14, resistance, contact D of jack 11, contact A of jack 10to tip of plug 6; and is also connected to the sleeve o1 both jack 11 and jack 10 over obvious circuits. The sleeve relay 7 is' adapted to .be operated, when the plug 6 is -insert-' ed in line jack 2, overacirc'uit extending from battery 41, resistance, winding B 0t line relay 4, sleeve of jackQ, sleeve of plug (1, winding of sleeve relay 7 to ground. lVith the plug 15 of the cord circuit X, relay 7 controls the supervisory lamps 8 and 9. These lamps are in a circuit dependent upon contacts A and B of sleeve relay 7 and contacts B and C of trunk jack 11, the

circuit being so arranged that the lamps will light if contact B of relay 7 and contact C of jack 11 are both closed, or if contact A of the relay and contact B of the jack are both closed. When closed, this circuit may be traced from grounded battery 12, through lamp 9, either contact B or contact C of jack 11, and either contact A or contact B of relay 7, lamp 8 to ground; As contact B of relay 7 is closed by the energization of that relay and opened by its deenergization;

while contact C is normally closed, but is opened by the insertion of the plug 15 into the jack 11, it is apparent that, in the case of an inward call from a subscriber, when the plug 6 is inserted in jack 2, lamps 8 and 9 will be lighted, when plug 15 is inserted in jack 11 they will be extinguished; when plug 15 is removed from jack 11 they will be relighted, and when plug 6 is removed from jack 2 they will be reextingushed. Also,

in the case of an outward call to-a subscriber, when plug 15 is first insertec in jack 11, lamps 8 and 9 will light, and then when plug 6 is inserted into jack 2, the lamps will be extinguished.

The cord circuit X includes trunk plugv 15 and toll plug 16, sleeve relay'l'? and supervisory lamp 18. The tip'ot plug 15 is connected through contact C of normally deenergized sleeve relay 17, through supervisory lamp 18 to grounded positive battery 21. The sleeve of plug 15 is connected through a winding of relay l7,resistance 19 to the sleeve of the toll plug 16. The tip of plug 16 is connected to normally open contact 13 of sleeve relay 1? and also through normally closed contact A of that relay and resistance to ground. r

The toll board Y comprises two sets of jacks, one of which has been described in connection with the switching trunk W, and the other of which is shown schematically by monitor jack 22 and toll line jack 23. Associated with the toll board Y is a haltdupleX set Z (not shown in full) whose function is to send or receive si nals over a line connecting with another central station. Since the structure and operation of a half-duplex set, as well as the manner of its association with a line, are well known a detailed description is omitted here. However, the sending relay 28 of the haltduplex set is shown in order to clarify the explanation of certain apparatus associated with the toll board Y. As is well known, the local loop extending from a halt duplex repeater consists of a normally closed circuit. This circuit is conventionally termed the receiving leg of the half-duplex repeater. The other loop of the half-duplex repeater is connected to the line circuit, extending to the other central station, in a manner well known in the art. This'other loop is also a closed circuit and is termed the sending leg. In the present embodiment, the receiving leg or loop 29 extends-from positive battery 30, winding of sending relay 28, conductor 29, winding of relay 26, contact'B of monitor jack 22 of the toll board, contact C of the line jack 23, through a resistance to ground. Individual to jacks 22 and 23 of the toll board is a combined calling and supervisory lamp 24 controlled by a slow-operating relay 25 which is, in turn, controlled by the relay 26 in the loop circuit 29. When the loop 29 is opened for a suliicient period, relay 26 releases and closes an obvious circuit for operating slow operating; rclav 25. Th s latter relay is also provided with a locking circuit which energizes through contact B of relay 25, contact A of mo ltor jack 22 to ground. Slow operating relay 25, ts A contact, closes. a circuit for supervisory lamp 24 which may be traced from grounded battery 27, lamp 24, contact A of relay 25, contact A of monitor jack 22 to ground.

Associated with the toll board is a monitor printer unit U of usual type. Th s unit comprises a plug '31, a printer including printing magnets 32 and transm tting contacts 33 connected in series with the tip station and at the additional subscribers stations can be readily understood from the preceding description, a detailed description of the apparatus at these stations is thought to be unnecessary.

The operation of the above described'systein, in the extension of a connection between subscribers stations, associated with separate central stations,tor example,'between a subscribers station located in New York and another subscribers station 10 cated in Chicago, will now be given in detail. J

The New York subscriber operates the key 42 which momentarily opens line 1, releasing line relay 4, short-circuiring the line winding A of that relay, so that it will not. be re-energized when the key 42 is re-closed. Upon the release of line relay 4, the calling lamp 3 is lighted, thus informing the concentration board operator that an incoming call is waiting on line 1.

The concentration board operator inserts the plug 43 of a printer cord circuit T, into the line jack 2 to answer the call.

The insertion of plug 43 into ack 2 opens the operating circuit of callingv lamp 3. The circuit from negative battery 5 isalso opened and the positive line battery 41 will now be supplied to tne subscribers line over a: circuit from positive battery 41, winding B of line relay 4, sleeve of jack 2, sleeveof plug 43, winding of relay 46, transmitter contacts 45, winding of printer magnets 44, tip of plug 43, tip of jack 2, line l, to the subscribers station The positive current now supplied from the centralstation starts the subscribers station printer as previously explained. Line relay 4 is energized and operates in response to line signals. The insertion of plug 43 into jack 2 also starts the cord circuit printer in the following manner: when the plug is inserted in the jack relay 40,'it pulls up and causesmomentary current impulse through condenser 47 to flow through the left-hand winding of relay 48. Relay 48 locks up through its righthand winding over an obvious circuit and eXtinguishes lamps 51 and 50. and at the same time through its left-hand tongue and contacts, closing a circuit to motor 49 which starts. The cord circuit printer and the subscribers printer are now operatively associated. The subscriber then requests a toll connection to Chicago, giving the Chicago number called. The recording operatorfills out a toll ticket giving this information and passes it on to the concentration board operator. The latter removes the recording printer cord circuit from the subscribers line jack 2. This releases relay 4 causing negative current to be applied to line 1 thus opening the operating circuit of the subscribers printer motor. However, as soon as the operator inserts the plug 6 of the switching trunk W into the jack 2 and thereby extends the circuit to the toll board Y, the sleeve relay 7 in the switching trunk operates over a circuit previously traced and positive battery 14 is applied to the subscribers line 1 over a circuit previously traced to the tip of plug 6 and thence through tip of jack 1 over line 1 of the subscribers station. The application of this battery to the line 1 restarts the subscribers printer motor 40 in the manner previously described. The operation of relay 7 lights supervisory lamps 8 and 9 over a previously traced circuit, and the latter informs the toll board operator that the particular switching trunk associated with the lamp 9 has been connectedto a subscribers line 1 atthe' concentration board Y. The concentration board operator writes the number of the switching trunk W on the toll ticket and tingui shed.

sends the ticket to the toll board operator.

The toll board operator seeing that the lamp 9 associated with the trunk jack 11 is lighted, plugs the trunk cord 15 of an idle cord circuit X into that jack. This opens the circuit of the lamps 8 and 9 at contact C of jack l1 and both of these lamps are ex- The sleeve relay 17 of the cord circuit X being unoperated at this time, positivebattery 21 is supplied through cord lamp 18, contact C of relay 17 through the tip of plug 15, tip of jack 11, contact A of the monitor jack 10 and to the subscribers station over a previously traced circuit, thus lighting lamp l8 and replacing battery 14 which has been disconnected from the subscribers line by the insertion of plug 15 into jack 11. In case the calling subscriber should wish to learn the status of his call to Chicago he can flash the lamp 18 by opening and closing the line 1. The toll operator, upon observing the flashing of the lamp can answer by plugging his monitor printer unit- U into the monitor jack 10 and convey to the calling subscriber the information he desires.

As soon as the toll operator receives the toll ticket he notes that the subscriber calling Chicago has been assigned the switching trunk W to which his answering plug 15 has been connected, and without further delay he proceeds to call Chicago by plugging his monitor printer U into the monitor jack 22 associated with one of the Chicago lines. The monitor printer U is thus placed in series with the local loop 29 over an obvious circuit, "and the operator opens this loop for a few seconds and then closes is by operating key 34. This causes the opening of the local loop associated with the Chicago toll board, upon which relay 26 in that loop releases, and after a suflicient interval causes the operation of slow operating relay 25 which looks up over a previously traced circuit. The operation of slow operating relay 25 completes a circuit, previously traced for the calling lamp 24. i The Chicago toll board operator answers by plugging his monitor printer U into the monitor jack 22 which connects the printer in series with the half-duplex. loop at the Chicago station, and extinguishes lamp 24 and releases relay 25 by opening their circuits at the A contact of the monitor jack 22. The Chicago operator then operates his'printer to signal the New York toll operator and the latter transmits the called subscribers number over the wire. Upon the receipt of this information, the Chicago toll board operator calls the local concentration board over an order wire (not shown) requesting the assignment of a switching trunk W to the called subscriber. The concentration board operator gives this assignment and plugs the assigned switching trunk 6 into the called subscribers jack 2 and the Chicago toll board operator plugs the trunk plug 15 of one of his cord circuits X into the trunk jack 11, associated with the assigned switching trunk WV, and plugs the toll plug 16 of the same cord circuit into the line jack 23 associated with the line extending to the New York station. At this point it may be noted that the resistance and ground associated with contact A of the sleeve relay 1? of the cord circuit X and resistance and ground associated with contact C of sleeve relay 7 of the switching trunk W serve to ground the loop circuit of the toll plug 16 of the cord circuit X is plugged into the line jack 23 before the trunk plug 15 is plugged into jack 11 or before the switching trunk "V has been connected to the called subscribers line 1 by means of plug 6 at the concentration board. Also, the connection'to positive battery through lamp 18 serves to hold the subscribers line closed if plugs 6 and 15 are both inserted into their respective jacks 2 and 11 before toll plug 16 is insertedinto the toll line jack 23. This arrangement makes it immaterial in what order the connections are made between the toll board at the called central station and the called subscribers station.

It should also be noted that lamps 8 and 9 are so connected that they will both light if either operator plugs up his end of the switching trunk before the other operator does so, and that both lights will be extinguished when both ends of the trunk are plugged up. These lamps, therefore, guard ilk 'tions.

against the possibility that either operator may plug up the wrong switching trunk. V

As soon as both of the plugs 15 and 16 of the cord circuit X are inserted in their appropriate jacks, 23 and 11, the sleeve relay 17 in the cord circuit operates over acircuit traced from grounded battery 14, through the sleeves of jack 11 and plug. 15, through winding of relay l7, resistance 19, sleeve of plug 16, sleeve of line jack 23 to ground. Just before completing the connection between the called parties, the Chicago toll operator signals the New York toll operator that the connection has been set up. The New York toll operator then calls the called subscriber in Chicago directly from his monitor printer unit U, and as soon as he obtains an answer inserts toll plug 16 ot the cord circuit X to which the New York subscriber has already been connected into the line jack 23 and advises both subscribers by printer to go ahead. Relay 17 operates and lamp 18 is extinguished. The New York toll operator times the start of the conversation and both toll operators remote their monitor printer plugs 31 from the monitor jacks 22 as soon as the communication between the two subscribers is satisfactorily started.

When the communication between the subscribers has been completed, the calling subscriber depresses his disconnect key 42 for several seconds, which opens the line 1, and consequently the loop 29 at both of the sta- The opening of these loops causes the release of relays 26 at both the New York and Chicago toll boards, and after an interval slow operating relays 25 energize and lock, lighting the supervisory lamps 2 1 at both, stations and giving the toll operators a disconnect signal. They immediately plug their monitor printers into the monitor jacks 22, extinguishing the lamps 24, and the toll operator at New York inquires whether or not communication has ended. Upon receiving acknowledgment that this is the case, the New York operator times the completion of the call and both toll operators pull down their respective cord circuits The removal of the toll plugs restores he respective loop circuits 29 to normal and r t the removal of the trunk plugs 15 from the trunk jacks 11 at both New York and Chicago causes the lamps 8 and 9 to light over a circuit previously traced, giving the 0011- centration board operators at both stations a disconnect signal. As soon as these operators pull down their respective plugs 6 from line acks 2 in the concentration board,

- both lamps 8 and 9 are extinguished, both subscribers printer motors are stopped by the removal of positive battery 14 from the line 1, and the reapplication of negative battery 5 to the line, and all circuits are restored to normal. 1

WVhat is claimed is: 2 v1 In a printing telegraph exchange system, a central station having a concentration board, a toll board and a terminal repeater, a switching trunk for interconnecting said boards,a cord circuit for interconnecting said toll board and said terminal telegraph repeater, and supervisory means in said switching trunk for indicating when said concentration board is connected tosaid toll board, when said concentration board is lishing a connection between said conce'n-i tration board and said trunk jacks, and a cord circuit for establishing a connection between said trunk jacks and said line jacks.

3. In a printing telegraph exchange system, a central station having a concentration board in which a plurality of subscribers lines terminate, a toll board with trunk and line jacks, terminal telegraph repeaters individually associated with said line jacks,

a plurality of switching trunks for connecting any one of the lines terminating in said concentration board to one of said trunk jacks, and a plurality of cord circuits for connecting any one of said trunk jacks to one of said line jacks and to the terminal telegraph repeater associated with said jack,

4. In a printing telegraph exchange sys tem, a central station having a 'concentra tion board and a toll board, a subscribers station connected to the concentration board by a normally closed line circuit, a printer included in the line circuit at the subscribers station, a motor for driving the printer,

and means responsive to a reversal of cur- 7 rent in the line circuit for starting the motor, a switching trunk for extending the line circuit to the toll board, a cord circuit for connecting the extended line circuit to a loop circuit of a terminal repeater, means effective when the switching trunk extends the subscribers line circuit to thetoll board for. reversing the current therein to start the printer motor, means etl'ective when the extended line circult 1s connected to the cord circuit, and other means eflective when theextended line c rcuit is connected to a loop.

circuit of the terminal. repeater, for maintaining the same direction of-current in the subscribers line circuit to keep the printer motor in operation. V

v.5. In aprinting telegraph exchange system, a manual switchboard provided with amonitor and a line jack, a terminal repeater having a firstclosed loop circuit connected to a line circuit and a second closed 6; In a printing-telegraph exchange system, a concentration board, a tool board, a switching trunk having one end terminating in a plug and the other end terminating in a jack on the tool board, said switching trunk having therein a relay energizable when said switching trunk plug is inserted in a jack on said concentration board and deenergizable when said switching trunk plug is removed therefrom, said toll board Jack 7 having a normally closed contact adapted to be opened and a normally open contact adapted to be closed when a cord circuit is connected thereto, a lamp associated with the plug of said switching trunk and another; lamp associated with saidtoll board jack, said lamps having a first operating circuit including a normally open contact of said relay and the first contact of said toll board jack and a second operating circuit including a normally closed contact of said relay and the second contact of said toll board jack.

7. In a printing telegraph exchange system,'a toll board, a terminal repeater associated therewith, said repeater having a first closed loop circuit connected to a line circuit and a second closed loop circuit extending through said toll board, a concentration board, a switching trunx, having one end terminatingin said toll board, for interconnecting said toll board and said concentration board, a cord circuit for interconnecting the toll board end of said switching trunk and the second loopof said tele graph repeater, and means for maintaining the second loop of said repeater closed when the cord circuit alone and when both the cord circuit and the switching trunk are con- "nected' to said second loop before said being started and maintained in operation- ZLIlClSZLld terminal repeater bemg maintained ALDER F; coNNERY,

switching trunk is connected to said concenand a concentration board, a terminal re peater associatedwith said toll board, a subscribers station connected to said central station by a lineterminating in said concentration board, a printer and a printer'motor at said subscribersstation, a switchingtrunk and a cord circuit, cooperating with tween said terminal repeater and said sub scribersline, said subscribers printer motor 

